Upgrading from 300mm to 320mm Rotors Need Caliper Mount Advice

[Old Jock]

So given that I've got a bad rotor and I'm thinking of replacing the current solid rotors to ISR full floaters. I thought this might be a good upgrade given the expense of the discs.

The Sfida already has ISR 6 pots, hence to make full use of the stopping power a larger diameter rotor can only be a plus

However I'm totally clueless about how or what would be required to move the calipers out to accommodate the new larger rotors and would appreciate any advice, generally on the mod and on the caliper mounting bracket. If its going to be more trouble than its worth then tell me that too. I'm asking for help here.

Here is the current set up with the 300mm rotors



This was taken before the tyres were fitted but shows the caliper mounting bracket quite well, I can take other photographs and measurements if required

[Oldrat]

Hiya
Ive put 320 rotors on my cafe tonti and can advise the obvious need to relocate the caliper.
youll need a different adaptor plate and will have to measure to get the mount locations right.
When i did mine i made the adaptors from wood to get the right measurements and fit, then got it machined up. Doing a mock up allows you to check that the new caliper
position doesnt foul the spokes.

Make sure that the new rotor has the same offset, (the amount the braking surface sits outside of the line of the mount holes whenviewed from the front)

Make sure you use suitable mounting bolts as the OEM are most likely high tensile for a reason.

[canuguzzi]

Did the brakes you had not do what you want?

[Old Jock]

Thanks OR very useful, sounds like a shed load of work mind.

NP the 6 pots are awesome but I'm afraid the Magni rotors have been a bit of a disappointment, which is very unusual for Magni parts. As it is I have a warp on one of the rotors that I need to investigate further and was thinking about the 320s to increase rotor cooling as well as additional stopping power. The difference in going from 300 to 320 is but a drop in the briny compared to the initial cost of either 300 or 320 fully floating rotors.

That said with the ISR 6 pots you see in the photo I had to haul the bike down from 70 to under 40 a few weeks back rapido, partly my stupid fault (a bit too close to the vehicle in front, preparing for an overtake but that's no excuse) and another idiot a few cars ahead standing on his brakes for no good reason.

Even with the badly warped rotor I was doing a stoppie and could fell the back end skipping and weaving through lack of traction. The Sfida, although looking light is incredibly heavy.............. .......I was well impressed the the way these calipers did their job. I just want to get rid of the bad pulse to smooth out braking making it more linear and controllable. Oh and pass my mandatory annual vehicle inspection, for which a pulsing lever will be a fail.

With my normal riding style I rarely use the brakes and rely on engine braking, if I'm grabbing a fistful then I've done something wrong. I'm not quick but I do like a flowing style of ride getting into a groove.

After a great deal of thought about getting the rotors skimmed etc: I'm thinking probably the best option (though far from cheap) is to stop throwing good money after bad bite the bullet and get a set of ISR full floaters.

[jacksonracingcomau]

Jock
OR is spot on, bear in mind bkt may have to be milled now not just drilled as yours is now. Will add to cost.
Discs look like OE Brembos from lm123, cast iron and good, if enough meat, I'd skim esp as you say you've got enough brakes,
Option 3 is 300 floaters, I have EBC ones, to fit 90's laverda (search here, how I found them)
Pretty sure your disc pattern same, measure offset to be sure of fit
I'm really happy with them.
If discs too thin, that would be easiest, 

[canuguzzi]

Yeah, the replacement you finally decided on will give you peace of mind and likely a better return on money put in.

No doubt after all is done, when you do grab a handful, at least it won't feel like a pogo stick.

[Oldrat]

My calipers and rotors are from a Ducati 916 and they look a treat.


RE warped rotors.
One of the main causes of warped rotors is hot spots.  The common cause is a period of heavy braking sufficient to make the rotor nice and hot, immediately followed by sitting (say at lights) stationary with the brake held on.
This allows the rest of the rotor to cool, but the section held under the brake pads stays toasty warm. The differential in temperature across the surface area lends itself to warping.